Which statement is true?

a.

opinions can be scientifically tested.

b.

scientific theories are absolute and cannot be changed.

c.

scientists have learned all they’ll ever know about science.

d.

facts can be scientifically tested.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

if you need further assistance, let me know: )

~ trueboss72